Western Star 47X 2020, Maintenance Manual

Page: 29 / 166

09–01 Air Cleaner Inspection
Restriction of air flow through the air cleaner element
is measured at the tap in the air cleaner outlet.
Check the restriction indicator at the air cleaner or in
the cab if the vehicle is equipped with a dash-
mounted restriction gauge.
Vehicles may be equipped with either a manual-reset
restriction indicator with graduations (
Fig. 1 ), or a
go/no-go restriction indicator without graduations
(
Fig. 2 ).
1. Inspect the air restriction indicator to see if air
restriction equals or exceeds the maximum al-
lowable restriction. For instructions, see
Group
09 of the Western Star 47X and 49X Workshop
Manual .
NOTICE
Do not use aftermarket air-cleaner elements. After-
market air-cleaner elements may not seal the
housing correctly, which can lead to engine dam-
age and potentially the loss of warranty. When re-
placing an air-cleaner element, use only the part
listed in PartsPro for the serial number of the ve-
hicle.
2. If necessary, replace the air cleaner element. For
air cleaner element replacement instructions.
3. Inspect the air cleaner housing for cracks, leaks,
or any other damage. If the air cleaner housing
or element is damaged, replace it.
4. Inspect the forward and rear mounting isolators
for damage. See
Fig. 3 . Ensure the bonds be-
tween the rubber and the steel plates are com-
pletely intact. See
Fig. 4 .
If a mounting isolator is damaged, replace it. For
isolator replacement instructions, see
Section
09.01 of the Western Star 47X and 49X Work-
shop Manual .
5. Check that the quick connect fitting for the air
compressor supply line is fully engaged with the
air cleaner. See
Fig. 5 .
6. The optional hood mounted pre-separators are
designed to be maintenance free. If the vehicle
experiences the following conditions, the pre-
separators should be removed, disassembled,
and if required, cleaned;
6.1 Exposure to highly dusty conditions a on
regular basis.
6.2 Shorter than expected filter intervals.
7. Reset the air restriction indicator.
8. Each time the air cleaner housing is replaced,
perform the procedures in
MOP 13–01 .
Pre-Cleaner Maintenance
If the vehicle often works in dusty conditions, or ex-
periences shorter than expected filter life, inspect the
cleaners for proper installation and internal dirt
build-up that could have an effect on their dirt re-
moval efficiency.
If the vehicle application exposes it to large, light
weight, debris that could pass over the hood air in-
take passages, and the driver reports significant
08/07/2007 f090452
Fig. 1, Manual-Reset Air Restriction Indicator,
Graduated
04/08/2005 f090431
Fig. 2, Manual-Reset Air Restriction Indicator, Go/
No-Go
Air Intake
09
47X and 49X Maintenance Manual, August 2020
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